In order to study the influence of ultrasonic vibration on the formation mechanism of the cross section of sawing monocrystalline silicon, the equation of cutting trace of abrasive grain in radial vibration rotary sawing process was presented, and the trace of abrasive grain was simulated using the MATLAB.The experiments of radial vibration rotary sawing and conventional sawing of monocrystalline silicon were carried out respectively. After sawing, the micrographs of the cross section surfaces were analyzed with SEM. The experimental results show that the scratches on the cross section produced by ultrasonic assisted sawing present a crisscross wave path, while the straight line shaped path is produced in the conventional sawing process. And the simulated consequences are compared with the formation of cross section and their microstructures are found to be in the same manner, which proved the validity of this analytical method.

radial vibration rotary sawing; monocrystalline silicon; trace of abrasive grain; formation of cross section